At least five bombs ripped through apartment buildings across Baghdad today and another struck a market, killing 49 people and wounding more than 160, authorities said. Iraqi officials blamed al-Qaida in Iraq for the violence, the latest sign the country's fragile security is dissolving in the chaos of the unresolved election. It was the fourth set of attacks with multiple casualties across Iraq in five days, a spate of violence that has claimed more than 100 lives. Attacks have spiked as political leaders scramble to secure enough support to form a government after the 7 March elections failed to produce a clear winner.

Ayad Allawi, whose bloc came out ahead in the vote by two seats over prime minister Nouri al-Maliki's, said the political deadlock was behind the new wave of violence. He also raised the prospect that the impasse could last for months as both sides try to cobble together the majority needed to govern.

"This is blamed on the power vacuum of course, and on how democracy is being raped in Iraq," Allawi said. "Because people are sensing there are powers who want to obstruct the path of democracy, terrorists and al-Qaida are on the go … I think their operations will increase in Iraq."

He added that he did not foresee any clear timetable to form a government. "It could either be formed in two months or it could last four or five months," he said.

Major General Qassim al-Moussawi, an Iraqi military spokesman for Baghdad's operations command centre, said the attackers detonated blasts using homemade bombs and, in one case, a car packed with explosives. He said there were at least seven blasts; the US Embassy in Baghdad said there were five.

Moussawi blamed al-Qaida in Iraq for the explosions and said Iraq was in a "state of war" with terrorists.

He said most of the buildings were two storeys high, but one in the Allawi district was five storeys.

Police and medical officials said the death toll from the explosions and the car bomb was at least 49, and that women and children were among the dead.

The explosions started at about 9.30am at a residential building in the Shula area of north-west Baghdad.

That was followed by a car bomb about a mile away at an intersection, which damaged nearby buildings, according to police and hospital officials who spoke on condition of anonymity because they were not authorised to speak to the press.

A few minutes later, at 9.45am, a bomb left in a plastic bag exploded at a restaurant in the Allawi district, near the culture ministry.

Ali Hussein, a student, 22, was taking the bus to college when one of the Shula bombs exploded.

"Cars began to collide with one another in the street because of fear," said Hussein, who fled for home after the blast. "We saw a cloud of fire and black smoke rising from a building at the explosion site, and while we were terrified by this explosion, another one took place."

Several hours later, a parked car bomb exploded in a market, killing six civilians, a police officer said.

On Monday, a Shia couple and four of their children were gunned down in their home outside Baghdad, while more than 40 were killed on Sunday after suicide attackers detonated three car bombs near embassies in the capital.

On Friday, gunmen went house to house in a Sunni area south of Baghdad, killing 24 villagers.